Extensible lamp-standard



NITED STATES PATENT FFICE.

MILLER M. DEEM, OF READING, PENNSYLVANIA.

EXTENSIBLE LAM P-STAN DARD.

SPECIFICATION forming part of Letters Patent No. 510,243, dated December 5, 1893. Application filed February 6, 1893. Serialll'o. 461,112. (No model.)

To all whom it may concern.-

Be it known that I, MILLER M. DEEM, a citinen of the United States, residing at Reading, 1n the county of Berks, State of Pennsylvania, have invented certain Improvements in Extensible Lamp-Standard s, of which the following 1s a specification.

This invention relates to that class of extensible standards for lamps in which two tubes are employed, one arranged to slide within the other, and in which the friction devices that serve to retain the tubes in any desired relative position are operated by means of a conveniently located lever carried by the sliding tube. V

The invention consists in certain improvements, first, in the friction devices by which the movement of the sliding tube is controlled, and second, in the lever mechanism for operating these devices.

The improvements are fully described in connection with the accompanying drawings and the novel features specifically pointed out in the claims.

Figure 1 is a sectional elevation of a standard embodying myinvention. Fig. 2 is a separate View of the lower end of the inner or sliding tube, and Fig. 3 a view of the friction or grip-plates and their carrier-head.

A represents the outer stationary tube and B the vertically movable inner tube upon the free upper end of which the lamp is carried. Between the wedge-shaped extensions 1) b at the lower end of the inner tube is located the cross-bar d of the grip-plate carrier-head D. This carrier head is adj ustably secured to the screw-threaded lower end of the upwardly extending rod 0 in the inner tube, and is provided with transversely oblong holes cl in which are movably mounted pivot pins 2' which pass through inwardly projecting ears e on the grip-plate E. The extended ends of these pins bear directly upon the inclined faces of the wedges b, upon which they ride up and down with the vertical movement of the carrier rod 0 to move the grip-plates E radially outward against the wall of the outer tube or to release them from contact therewith as desired.

The grip-plates E as shown are provided with surfaces e and e to bear against the curved wall of the stationary tube A, both of said surfaces being correspondingly curved so as to have contact with a considerable extent of said wall and one of them being formed with a gripping edge as seen ate to more certainly prevent accidental movement of the tube when adjusted to any desired height. The pivot pins 11 lie between the surfaces e, 6 so that the'grip-plates rock thereon to ad just themselves to proper contact with the stationary tube.

The rod 0 passes through a shelf g forming:

part of a bracket piece G which is fixed to the inner wall of the tube B by means of a screw 9 Near its upper end it is provided with a fixed collar 0 and its extreme end is notched as shown at c to permit of its being turned by means of a screw-driverintroduced at the upper end of the tube, for the purpose of raising or lowering the carrier-head D to properly adjust the grip-plates upon the wedges b.

At 9 upon the upper end of the bracketpiece G and close to the wall of the tube, is pivoted an operating lever F for depressing the rod 0 to release the grip-plates, said rod being normally raised by means of a spring H which is seatedupon the shelf g and presses upward against the collar 0 of the rod. The main portion of the lever F extends upward, lying close to the wall of the tube B, and is provided at its upper end with a push button f which projects through a hole 12' in the tube.

This button serves as a means of working the lever upon the pivot g, so that the right angled arm f thereof, which rests upon the collar 0, may be caused to depress the rod against the upward pressure of the spring and release the grip-plates by lowering the pins 71 which ride upon the wedges b, toward the reduced lower ends thereof.

By means of my lever arrangement for operating the rod 0 the appearance of the standard is improved, the projecting buttonf being neat and unobstrusive and serving to entirely hide the opening b through which it passes. The grip-plates maintain a thoroughly reliable hold upon the-walls of the tube and are'readily adjusted to proper gripping position without taking the standard apart, and the whole mechanism is cheap and compact, readily applied, and reliable in operation.

Having thus described my invention in its preferred form I do not limit myself to the exact construction shown, but

What I claim, is

1. In an extensible lamp standard substantially as described the combination with the inner tube and the operating rod for the grip mechanism between the tubes, of the bracket G fixed within said inner tube, the lever F pivoted thereto and bearing upon the end of the rod, and the rod retracting spring seated upon said bracket, substantially as set forth.

2. In an extensible lamp standard having an outer tube and an adjustable inner tube provided with wedge-shaped end I) the grip plates E with bearings e e pivoted to the end of the vertically movable rod 0 by means of pins which pass through ears on the grip plates and through transversely oblong holes in the end of said rod, the projecting portions of said pins being arranged to ride upon the inclined faces of the Wedge shaped end of the tube whereby the movement of said rod is caused to apply or release the grip-plates, substantially as set forth.

In testimony whereof Iaffix my signature in presence of two witnesses.

MILLER M. DEEM. \Vitnesses:

JOSEPH A. ALLGAIER, JOSEPH F. McOoNNELL. 

